To be clear, none of this is exactly new, but John Mueller of Google took the time to explain how mobile-first indexing works with mobile-first indexing. Most sites have been switched over to mobile-first indexing but if you have not, then here is what you need to know specific to m-dot or separate mobile URLs.

That last link tells you everything you need to know.

I am not going to cover this in detail again but use that Google resource if you are worried.

As a reminder, Google is going all in on mobile-first indexing March 2021 after giving us an initial deadline of September 2020. This initiative was first announced in 2016 – so we had plenty of time to prepare.

Forum discussion at Twitter.